A transportation network for vehicles can include several interconnected main routes on which separate vehicles travel between locations. For example, a transportation network may be formed from interconnected railroad tracks with rail vehicles traveling along the tracks. The vehicles may travel according to schedules that dictate where and when the vehicles are to travel in the transportation network. The schedules may be predetermined in order to arrange for certain vehicles to arrive at various locations in the transportation network at desired times and/or in a desired order.
A network planning algorithm may be used to coordinate the schedules of several vehicles in the transportation network. One goal of the network planning algorithm may be to coordinate the schedules to avoid significant slowdowns or congested areas in the flow of movement in the transportation network. For example, the network planning algorithm may seek to arrange the schedules so that the vehicles are able to move to associated destination locations as quickly as possible.
Other algorithms may be used in conjunction with the travel of the vehicles to reduce fuel consumed by the vehicles. For example, a fuel optimization algorithm may be used to determine the speeds at which the vehicles are to travel to a destination location in order to reduce the amount of fuel consumed relative to traveling to the destination location at one or more other speeds. One goal of the fuel optimization algorithm may be to reduce the amount of fuel consumed as much as possible while still allowing the vehicles to reach associated destination locations.
When used together, the network planning algorithm and the fuel optimization algorithm may have competing goals. On one hand, the network planning algorithm may seek to get all vehicles to associated destination locations as quickly as possible, regardless of the amounts of fuel consumed by the vehicles. On the other hand, the fuel optimization algorithm may seek to get the vehicles to the associated destination locations while reducing fuel consumption. The fuel optimization algorithm may cause the vehicles to slow down and, as a result, arrive at the destination locations later than the vehicles could have otherwise arrived.
The goals of the network planning algorithm and the fuel optimization algorithm compete with each other and may result in one or both of the algorithms failing to reach the associated goals. A need exists for coordinating or harmonizing the goals of the different algorithms so that vehicles can travel to destination locations while reducing the amounts of fuel consumed, without significantly slowing the flow of travel of the vehicles in the transportation network.
As the vehicles travel through the transportation network, unforeseen or unplanned events may occur. For example, vehicles may mechanically break down (and slow down to run at a reduced capacity or stop movement completely), sections of the routes in the transportation network may become damaged, additional vehicles may enter into or pass through the transportation network, and the like. These events may disrupt travel of the vehicles in the transportation network. As this travel is disrupted, traffic or congestion of the vehicles may increase, thereby decreasing the flow of vehicles in the transportation network.
If traffic or congestion of the vehicles in the transportation network increases, the vehicles may be forced to abruptly slow down or stop movement in order to avoid collisions with other vehicles or to avoid coming within a predetermined distance or buffer from other vehicles. Such slowing down or stopping can cause the vehicles to consume fuel in relatively inefficient manners, which can increase the amount of fuel consumed in order to get the vehicles to the scheduled locations.
A need exists for scheduling travel in transportation networks that can adapt to changing circumstances, such as the detection of events that disrupt the travel of vehicles in the transportation networks.